WEATHERING OF CLAY MINERALS IN PODZOLS FROM THE APPALACHIAN HIGHLANDS

1974 ◽  
Vol 54 (4) ◽  
pp. 395-401 ◽  
Author(s):  
C. R. DE KIMPE
Keyword(s):  
Heat Treatment ◽  
Clay Minerals ◽  
Clay Fraction ◽  
Heat Treatments ◽  
X Ray Diffraction ◽  
X Ray ◽  
Early Stages ◽  
Mineralogical Properties

The clay fraction from various horizons of two Podzols sampled in the Appalachian Highlands was analyzed by X-ray diffraction and by a quantitative mineralogical procedure. Different cation saturation and heat treatments made it possible to detect differences in the mineralogical properties of the clays of the Ae horizon, but did not cause appreciable differences in the spectra of B and C horizon samples. In the Ae horizon, the clays were shown to have properties of both vermiculites and smectites. The paragonite-like structure induced by Na-saturation and moderate heat treatment is characteristic of minerals in the early stages of weathering from dioctahedral illites.

scholarly journals The Occurrence of Authigenic Clay Minerals in Alkaline-Saline Lakes, Pantanal Wetland (Nhecolândia Region, Brazil)

Minerals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 718
Author(s):  
Isis Armstrong Dias ◽  
Leonardo Fadel Cury ◽  
Bruno Guimarães Titon ◽  
Gustavo Barbosa Athayde ◽  
Guilherme Fedalto ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Clay Minerals ◽  
Saline Lakes ◽  
Clay Fraction ◽  
Water Bodies ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Fine Clay ◽  
Pantanal Wetland

Mg clay minerals are usually associated with carbonates in alkaline-saline environments, precipitated from solution and/or transformation from other minerals. The aim of this research is to identify the mineralogy and geochemistry of clay minerals in different alkaline lakes in the Nhecolândia region, the southernmost region of the Pantanal wetland (Brazil). Sediment samples were analyzed by X-ray diffraction, X-ray fluorescence, scanning electron microscopy and transmission electron microscopy. Water samples were analyzed, determining their main cations and anions, in order to understand their relationship with the clays. The analyses allowed classifying the water bodies as saline, oligosaline and freshwater lakes. The sediments are composed mainly of quartz and a fine-clay fraction, dominated by illite, kaolinite and smectite. The XRD results showed illite and smectite mixed-layered in the saline lakes at Barranco Alto farm, whereas at Nhumirim farm, trioctahedral smectite was only observed in one lake. The smectite minerals were normally identified coupled with calcite at the top of the sequences, associated with exopolymeric substances (EPS) in the lakes, suggesting that these minerals are precipitating due to the physical-chemical and biological conditions of the water bodies.

scholarly journals Mineralogy of the clay fraction of Alfisols in two slope curvatures: III - spatial variability

2013 ◽  
Vol 37 (2) ◽  
pp. 295-306 ◽  
Author(s):  
Livia Arantes Camargo ◽  
José Marques Júnior ◽  
Gener Tadeu Pereira
Keyword(s):  
Spatial Variability ◽  
Iron Oxides ◽  
Spatial Dependence ◽  
Clay Fraction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Half Height ◽  
Mineralogical Properties ◽  
Crystallite Dimension ◽  
Xrd Patterns

A good knowledge of the spatial distribution of clay minerals in the landscape facilitates the understanding of the influence of relief on the content and crystallographic attributes of soil minerals such as goethite, hematite, kaolinite and gibbsite. This study aimed at describing the relationships between the mineral properties of the clay fraction and landscape shapes by determining the mineral properties of goethite, hematite, kaolinite and gibbsite, and assessing their dependence and spatial variability, in two slope curvatures. To this end, two 100 × 100 m grids were used to establish a total of 121 regularly spaced georeferenced sampling nodes 10 m apart. Samples were collected from the layer 0.0-0.2 m and analysed for iron oxides, and kaolinite and gibbsite in the clay fraction. Minerals in the clay fraction were characterized from their X-ray diffraction (XRD) patterns, which were interpreted and used to calculate the width at half height (WHH) and mean crystallite dimension (MCD) of iron oxides, kaolinite, and gibbsite, as well as aluminium substitution and specific surface area (SSA) in hematite and goethite. Additional calculations included the goethite and hematite contents, and the goethite/(goethite+hematite) [Gt/(Gt+Hm)] and kaolinite/(kaolinite+gibbsite) [Kt/(Kt+Gb)] ratios. Mineral properties were established by statistical analysis of the XRD data, and spatial dependence was assessed geostatistically. Mineralogical properties differed significantly between the convex area and concave area. The geostatistical analysis showed a greater number of mineralogical properties with spatial dependence and a higher range in the convex than in the concave area.

scholarly journals Mineralogical Study of Levels with Magnesian Clay Minerals in the Santos Basin, Aptian Pre-Salt Brazil

Minerals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 970
Author(s):  
Maurício Dias da Silva ◽  
Márcia Elisa Boscato Gomes ◽  
André Sampaio Mexias ◽  
Manuel Pozo ◽  
Susan Martins Drago ◽  
...  
Keyword(s):  
Clay Minerals ◽  
Clay Fraction ◽  
Total Sample ◽  
Petrographic Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mineralogical Study ◽  
Original Rock ◽  
Mixed Layers

The object of this study is magnesian clay minerals present in carbonate rocks of the post-rift phase of the pre-salt in the Santos Basin. These rocks developed in an Aptian-age alkaline lacustrine environment. This study summarizes the formation of clay minerals associated with different lithotypes in a range of 19 m and a depth of more than 5100 m. They were characterized from petrographic analysis by optical microscopy, X-ray diffraction (total sample and clay fraction), and modeling by Newmod®; and examined and analyzed by scanning electron microscopy. An approach based on identifying lithotypes and characterization of microsites allowed us to understand the occurrence of different clay minerals. Kerolite was the most abundant mineral in the sampled range. It occurs in lamellar aggregates under greater preservation of the original rock lamination and in association with spherulites and shrubs. The Stv/Ker mixed layers occurs in the same association, and formed finer unlaminated aggregates associated with the more intense dolomitization and silicification processes. Saponite occurs associated with detrital minerals forming clayey levels intercalated with microcrystalline carbonates. Fluids with a high Mg/Si and pH < 9 favor the precipitation of kerolite. The increase in pH during diagenesis may be responsible for the formation of Stv/Ker mixed layers.

scholarly journals Heat Treatment Effect in the Corrosion Resistance of the Al-Co-Mn Alloys Immersed in 3 M KOH

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
J. G. Pereyra-Hernández ◽  
I. Rosales-Cadena ◽  
R. Guardián-Tapia ◽  
J. G. González-Rodríguez ◽  
R. López-Sesenes
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Chemical Analysis ◽  
Polarization Resistance ◽  
Electrochemical Techniques ◽  
Corrosion Current ◽  
Heat Treatments ◽  
X Ray Diffraction ◽  
X Ray ◽  
Co Concentration

Al-based alloys named M1, M2, M3, M4, and M5 doped with different atomic percentage (at%) of cobalt and manganese as cast and submitted at two heat treatments (600°C and 1100°C) were analyzed by using electrochemical techniques to evaluate their corrosion resistance immersed in 3 M KOH. With the heat treatments applied to the alloys, the sample M2 (65% Al, 20% Co, and 15% Mn) observed the highest corrosion resistance with R p values of 3.0 × 10 2 , 6.2 × 10 2 , and 1.61 × 10 3   Ω · c m 2 as cast, 600°C, and 1100°C, respectively. The latter was in agreement with the I corr calculated from the polarization curves where the values decrease based on the heat treatment applied as follows: 1.60 × 10 3 > 6.16 × 10 2 > 3.07 × 10 2   mA / c m 2 for 1100, 600, and as cast, respectively. Co concentration above 20% increases the corrosion current ( I corr ) and decreases the polarization resistance of the remain samples. The chemical analysis done with EDS and X-ray diffraction made confirmed the presence of compounds such as CoAl, Co2Al5, Co2Al9, MnAl4, and MnAl6.

scholarly journals ÍNDICE DE CRISTALINIDADE DA ILITA E CARACTERIZAÇÃO DOS ARGILOMINERAIS DA FORMAÇÃO PIMENTA BUENO – BACIA DOS PARECIS

2016 ◽  
Author(s):  
Jéssica Melanya Sisti de Paiva ◽  
Gislaine Amorés Battilani ◽  
Rubia Ribeiro Viana ◽  
Maurício José dos Reis
Keyword(s):  
Clay Minerals ◽  
Clay Fraction ◽  
X Ray Diffraction ◽  
Average Width ◽  
X Ray ◽  
Kübler Index ◽  
Half Height ◽  
Intracratonic Basins ◽  
Bottom To Top

ResumoA Bacia dos Parecis é uma das maiores bacias intracratônicas brasileiras e poucos são os estudos relacionados à sua gênese. A Formação Pimenta Bueno, objeto desse estudo, é constituída, da base para o topo, de calcários, folhelhos, siltitos e arenitos. O presente estudo tem como principal objetivo estimar o provável estágio diagenético/metamórfico em que essas rochas foram submetidas, por meio do estudo de difratogramas de raios-X da fração argila e dos parâmetros do Índice de Kübler (Índice de Cristalinidade da Ilita). Os resultados indicam que essas rochas encontram-se na Epizona e, a média das medidas da largura a meia altura (FWHM) é de 0,16°. A análise de difratometria de raios – X indicou a presença de clorita, ilita, pirofilita, caulinita e esmectita (montmorilonita). Além das espécies bem definidas, identificou-se, também, argilominerais interestratificados de ilita/esmectita e clorita/esmectita.Palavras Chave: Cristalinidade da ilita; Bacia dos Parecis; Formação Pimenta Bueno.AbstractINDEX CRYSTALLINITY OF ILLITE AND CHARACTERIZATION CLAY MINERALS OF PIMENTA BUENO FORMATION – PARECIS BASIN. The Parecis basin is one of the largest Brazilian intracratonic basins and few are the studies related to its genesis. Pimenta Bueno Formation, object of this study, is represented, from bottom to top, by limestones, shales, siltstones and sandstones. To achieve the objectives of this study, knowing the diagenetic stage and / or metamórphic degree to which were subjected the Parecis Basin rocks, were developed diffraction studies of X-ray of the clay fraction, followed by the calculation of the Kübler Index parameters (crystallinity of iIlita). The results indicated that these rocks are at the Epizone and the average width measured at half height (FWHM) is 0.16 °. The X-ray diffraction indicated the presence of the chlorite, illite, pyrophyllite, kaolinite and smectite (montmorillonite). Likewise were identified interstratified phases of Illite/ smectite and chlorite / smectite.Keywords: Crystallinity of Ilita; Parecis Basin; Pimenta Bueno Formation.

scholarly journals Study the Effect of Diffusion Heat Treatments for Nickel Electroplating on the Surface Hardness of 7075 Aluminum Alloy

2016 ◽  
Vol 63 ◽  
pp. 13-21
Author(s):  
Fouad El Dahiye ◽  
Almohanad Makki ◽  
Mohamad Yehea Alnefawy
Keyword(s):  
Heat Treatment ◽  
Aluminum Alloy ◽  
Surface Hardening ◽  
Intermetallic Phase ◽  
Surface Hardness ◽  
Heat Treatments ◽  
Effect Of Temperature ◽  
7075 Aluminum Alloy ◽  
X Ray Diffraction ◽  
X Ray

In this research a surface hardening process by Ni coating and subsequent diffusion heat treatments was studied at 7075 Aluminum alloy. Nickel coatings with different thickness were obtained by change the coating time and current density. Heat treatments at 450 °C, 500 °C, and 550 °C for times (6, 12, 24) hours were performed in order to obtain surface hardening required of the aluminum alloy by diffusion of nickel into the substrate. The effect of temperature and diffusion time on surface hardness of Al 7075 alloy was studied. Surface hardness about 800 [HV] were achieved after heat treatment at 500 °C for 24 hour by diffusion of Ni in the substrate and cause of formation of Al3Ni2intermetallic phase, as x-ray diffraction tests of samples showed. While is about 670 [HV] after heat treatment at 550 °C for 24 hour because of diffusion of aluminum toward the surface of sample, as x-ray diffraction tests of samples showed.

scholarly journals Fabrication of TiO2Crystalline Coatings by Combining Ti-6Al-4V Anodic Oxidation and Heat Treatments

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
María Laura Vera ◽  
Mario Roberto Rosenberger ◽  
Carlos Enrique Schvezov ◽  
Alicia Esther Ares
Keyword(s):  
Heat Treatment ◽  
Anodic Oxidation ◽  
Heat Treatments ◽  
The Other ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray ◽  
Heat Treated ◽  
Natural Oxide ◽  
Scanning Electron

The bio- and hemocompatibility of titanium alloys are due to the formation of a TiO2layer. This natural oxide may have fissures which are detrimental to its properties. Anodic oxidation is used to obtain thicker films. By means of this technique, at low voltages oxidation, amorphous and low roughness coatings are obtained, while, above a certain voltage, crystalline and porous coatings are obtained. According to the literature, the crystalline phases of TiO2, anatase, and rutile would present greater biocompatibility than the amorphous phase. On the other hand, for hemocompatible applications, smooth and homogeneous surfaces are required. One way to obtain crystalline and homogeneous coatings is by heat treatments after anodic oxidation. The aim of this study is to evaluate the influence of heat treatments on the thickness, morphology, and crystalline structure of the TiO2anodic coatings. The characterization was performed by optical and scanning electron microscopy, X-ray diffraction, and X-ray reflectometry. Coatings with different colors of interference were obtained. There were no significant changes in the surface morphology and roughness after heat treatment of 500°C. Heat treated coatings have different proportions of the crystalline phases, depending on the voltage of anodic oxidation and the temperature of the heat treatment.

Clay minerals in the agricultural surface soils in the Central United States

Clay Minerals ◽  
2001 ◽  
Vol 36 (3) ◽  
pp. 277-294 ◽  
Author(s):  
B. Velde
Keyword(s):  
United States ◽  
Clay Minerals ◽  
Agricultural Soils ◽  
Clay Fraction ◽  
Clay Mineralogy ◽  
Parent Material ◽  
X Ray Diffraction ◽  
Charge Site ◽  
X Ray ◽  
Central United States

AbstractA survey of the clay fraction at the surface of 86 loam and silt loam agricultural soils from the Central United States was undertaken to observe the possible influences of climate and parent material (dominantly phyllosilicates in this study) on the clay mineralogy of the upper portions of the soils, for the most part in Mollisol–Alfisol order soils.Decomposed X-ray diffraction spectra show that the most abundant clay minerals are two disordered illite-smectite (I-S) minerals, one with ∼50% smectite layers and another, less abundant, disordered I-S phase with 20% smectite. These minerals usually co-exist in the same samples. The charge site in both of these I-S minerals is both beidellitic and montmorillonitic in the expanding layers. A relatively large proportion of these smectite layers (up to 20%) are of high charge.There seems to be a convergence in mineralogy towards mixed-layer phases formed under a range of mid-Continent climates from a range of phyllosilicate parent materials.

scholarly journals Clay minerals from Weichselian glaciolimnic sediments of the Sępopolska Plain (NE Poland)

2009 ◽  
Vol 60 (3) ◽  
pp. 263-267 ◽  
Author(s):  
Jacek Dlugosz ◽  
Miroslaw Orzechowski ◽  
Miroslaw Kobierski ◽  
Slawomir Smolczynski ◽  
Ryszard Zamorski
Keyword(s):  
Clay Minerals ◽  
Clay Fraction ◽  
X Ray Diffraction ◽  
Complex Composition ◽  
X Ray ◽  
Ne Poland ◽  
Northeastern Poland ◽  
Main Components ◽  
Weichselian Glaciation ◽  
Similar Complex

Clay minerals from Weichselian glaciolimnic sediments of the Sępopolska Plain (NE Poland)Glaciolimnic deposits sampled from three sedimentation reservoirs located on the Sępopolska Plain (northeastern Poland) were investigated. The material under study was deposited in the recession phase of the Pomeranian phase of Vistula (Weichselian) glaciation. The clay fraction was separated by centrifugation after preparation according to Jackson. Mineralogical investigations were done by X-ray diffraction. The analysed deposits had a similar complex composition of clay minerals. The main components were illites mixed with the illite/smectite mineral with percentages < 10 % S. Another part were minerals of the illite/smectite type which had differentiated content of smectite layers (mainly 80-90 % S). There were also chlorite minerals, probably as mixed layer minerals of the chlorite/vermiculite type or HIV with a negligible amount of chlorite layers. The results indicated that all the deposits were of the same age as well as similar deposited material and the samples are different from typical Pomeranian till and typical limnic material of the same age. Small differences observed among the deposits of specific sedimentation reservoirs were probably the result of later processes.

scholarly journals Synthesis and Characterization of Hydroxyapatite Derived from Milkfish Bone by Simple Heat Treatments

2021 ◽  
Vol 12 (2) ◽  
pp. 2440-2449
Keyword(s):  
Heat Treatment ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Heat Treatments ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
Chanos Chanos ◽  
X Ray ◽  
Before And After

The present study aimed to synthesize hydroxyapatite (HAp) from milkfish (Chanos chanos) bone by simple heat treatments ranging from 600 to 800 °C. The yield and color of synthesized powders before and after heat treatment were analyzed. The synthesized powders were characterized using Fourier transform infrared spectroscopy (FTIR) to identify the functional groups and X-ray diffraction (XRD) was employed to identify phase and crystallinity properties. This study found that the yield percentages were found to be approximately 50%. The FTIR characteristics exhibited the phosphate and carbonate groups at high temperatures (≥600 °C). In general, this study confirmed that the well-crystallized HAp can be synthesized by thermal treatment at a temperature of 160 °C for 48 h.

Sign in / Sign up

Export Citation Format

Share Document